The present invention relates generally to high temperature superconductors. More specifically, the present invention relates to a melt-produced, high temperature superconductor and processes for making same.
Recently, there has been much work done on the utilization of ternary oxides containing copper, barium, and rare earth elements for superconductivity at temperatures above 90.degree. K. with the belief that superconductivity at or above room temperature is possible. Some of this work has centered on the utilization of a yttrium (Y)-barium (Ba)-copper (Cu)-oxygen (O) system.
Current developments of the Y-Ba-Cu-O class of ceramic superconductors have yielded optimistic results. These systems are typically created utilizing bulk materials which are powders or very small granule substances. These powders must be compressed to facilitate measurements and are relatively intractable. As can be appreciated, the structure of these substances is not conductive to the manufacturing of components from these ceramic superconductors.
A melt-produced, high temperature superconductor would be desirable for many reasons. Melt-produced superconductors would: (1) allow the growth of large bulk single crystals--this is important because it could facilitate the discovery of the correct theory on superconductivity; (2) provide low cost processing and manufacturability; (3) allow components to be cast in any shape; (4) allow the addition of other components to the melt-produced high temperature superconductors--this would allow one to create an extrudeable composition allowing the superconductor to be useful in the manufacture of superconducting wires, magnets, etc.; and (5) the inventors believe, allow for high critical currents in the high temperature superconductor allowing the generation of large currents therethrough.
Accordingly, there is a need for melt-produced high temperature superconductors and processes for making same.